Horse Sense: When asked how many races they'd won, the Agent 47 team said, "We'd have a lot more [wins] if Rocco [the AIX National Champion] wasn't there. But he's cool. He's our carrot. He has a light car and has been racing for years."

Race cars come in a variety of flavors. Some are pretty, some are gritty; some win races and some barely run. People gravitate toward the showy winners, but we also have a soft spot for those workman-like machines that aren't overly polished but run hard and exhibit creative craftsmanship. It's probably because many of our own race cars have been more purposeful rather than beguiling.

Agent 47 (www.agentfortyseven.com), the innovative, fairly new, Carlsbad, California-based Mustang specialist, has such a race car. It's what's left of a '94 Mustang built to the max for NASA's American Iron Extreme class. It's quick and handsome in a black and aluminum chic that says it's all business.

Those lucky enough to be at the track will instantly add the car's snarling, high-decibel exhaust signature to their assessment of the Agent 47 car's purpose. It's a particularly aggressive pair of pipes. Once the ignition is off and the car is quiet enough to approach, a close examination shows the Agent 47 machine is studded with tricks. From the NASCAR-like rollcage, widened hood, vortex generators, floating rear decklid, fender vents, and hood fences, and on to Agent 47's major fare, including the A-arm front and three-link rear suspension, this car bristles with crafty speed trinkets.

To understand all these parts, we should begin by saying that Agent 47 is a partnership of Corey Weber, Bill Osborne, and Heath Oyama. While others help, for example, Todd Harveston fabricates and Jerry Taylor puts in hours working out parts in CAD, Corey, Bill, and Heath are the principles. So far, their business is true specialty parts for Mustangs, including the pieces that don't fit into larger aftermarket outfits' product lines or items too racy or innovative for the bolt-on giants. The race car is the company's test mule and showcase.

The Agent 47 crew looks the contemporary part-goatees and ear studs here and there-except for Bill. He's old school, and we're sure he doesn't mind that coming from our gray selves. He has a long, storied career fabbing together all sorts of circle track, Trans Am, and other race cars. Bill is a whiz chassis man and the brains behind the race car's 'cage structure and suspension geometry. He has a pragmatic eye for assembling hardware that works without a moon-shot budget and is just the sort of character we'd befriend if trying to roll our own Mustang chassis.

What he's wrought started out as an American Iron car. Initially it was fitted with Agent 47's "inner frame," a substantial bit of iron works that's proved expensive for the street and over-built for a race car getting a 'cage, but it's ultra rigid. To this, Bill added his carefully designed rollcage/chassis and his own lightweight, three-link rear suspension, which features aluminum arms long enough to reach the front seats from the rear axle. A stock-block, 331ci noisemaker from Auto Dynamics was installed. From there, the Agent 47 guys spent all their time trying to reduce its power. American Iron has a power-to-weight-ratio rule, and with a 2,780-pound car, it doesn't take anything from a pushrod Ford small-block to earn the NASA tech inspector's disdain. Join Auto Dynamics background in Winston Cup and lightweight drag engines with Agent 47's zeal, and the engine simply wasn't basic enough.

After pinching this and choking that and still coming up with too much power, Corey and the Agent 47 gang decided American Iron Extreme was more their style. Extreme has no power limit, and the freer chassis and tire rules better accommodate Corey's tinkering tendencies (imagine a mechanical engineer at play and you have the idea). Thus, the engine was rebuilt into its now-snarling self by Auto Dynamics but retaining the paid-for iron block. Ported AFR heads, a cam with more than 0.700 inches of lift, custom shaft rockers, an Aviad dry sump, custom headers, 12.5:1 compression, and a Holley carb on an Edelbrock Victor Jr. intake manifold explain all the underhood racket.

Writing a $3,000 check at Tilton took care of the bellhousing, starter motor, flywheel, 5.5-inch three-plate clutch, and annular throw-out bearing, not to mention a place to hang the Tex Racing T101 four-speed Jerico-style transmission. This is a dog-gear racing box that shifts clutchlessly like hot butter. Agent 47's own carbon-fiber shifter handle is used to bring the stick to where Corey needs it.

In back, a Speedway Engineering 9-inch differential and axles take all the guff. The 9-inch was chosen because of the huge number of gear ratios available, something that is likely needed for fine tuning due to only four gears in the transmission. To date, they've found four rear-axle ratios necessary for the tracks they run, so they carry four 9-inch centersections that are so equipped. That and 9-inch parts can be had at reasonable prices anywhere racers congregate. Also reasonable is the spool; it might as well be free when compared to a high-torque, combat-capable, limited-slip differential.

Strut front suspensions are now rare in AIX, having been supplanted by A-arm replacement suspensions with their ability to reduce understeer and keep 315/30-18 front tires flat on the asphalt. Accordingly, Agent 47 developed its own A-arm front suspension with an eye on low cost and simplicity. They wanted an A-arm front-end a Mustang enthusiast could bolt into his street car, yet was race-proven and not wallet-busting at $2,500. The stock steering rack was retained, and the stock spindle was cut and welded to accept the tie-rod end at the proper angle. The entire A-arm assembly-spindle-to-spindle, including the K-member-was designed in Solid Works as far as the flat plates go, with the rest coming from Bill's shoulder-mounted computer. The system fits SN-95 cars for sure; it should fit Foxes without angst and will be adapted to S197s soon.

Braking is partly from the Mustang aftermarket and partly from circle track. In front are Baer Brakes 14-inchers wearing six-piston 6S calipers. The 6S is a street caliper, but it differs from the more appropriate 6R caliper, mainly in minor hardware and therefore rapidity of pad changes. Baer supplied the 6S calipers in the rush before the SEMA show, where the racer was on display, as 6R calipers weren't yet available, and they proved fine. In back, the 12-inch discs and four-piston Outlaw calipers are "econo" circle-track fare. Tilton's twin master-cylinder and balance-bar arrangement operates the system.

Poking around the bodywork, you encounter tricky Agent 47 parts. First up is something not casually evident: a hood 5 inches wider than stock. This one-off, not-for-sale Agent 47 hood is used to widen the bodywork while retaining stock fenders, which is cost effective. By mounting the front of the hood as low as possible relative to the fenders and fitting small aluminum fences between them, Agent 47 has turned the entire front of the hood into a downforce-producing wedge. The fenders are carbon-fiber Tiger Racing parts, as are the doors, trunk lid, and rear fender flares. The rear-quarter delete is an Agent 47 part, available with or without NACA ducts. It's ABS plastic.

Getting the bodywork behind the hood to line up was fairly easy, given the extensive rollcage structure. The doors and rear fenders were mounted wider on the tubular structure to accommodate the front fenders. That leaves the windshield and roof, which are stock parts in their stock locations. Even so, the roof was cut off during construction so it could be gutted of any reinforcing structure, and it made welding the 'cage much easier. Once the 'cage was built, the roof skin was welded back onto the chassis.

Atop the trailing edge of the roof is a row of Agent 47 vortex generators. Their job is to produce vortices in the wind flow. The vortices, small horizontal tornados, organize and bend the airflow down the backside of the roof, keeping the slipstream more closely attached to the bodywork. This fills in the dead air space behind the rear window-the area that doesn't get wet when you drive down the freeway in the rain-thus reducing aerodynamic drag and increasing the rear wing's effectiveness.

The wing is not stuck up there for looks. Its mounts extend to the trunk lid, where underneath, they mate to a compact triangular, tube-steel truss on each side. The trunk lid is hinged at the front, but the back two "feet" of the trusses rest on pressure transducers, which are wired to a display in the cockpit. Thus, the rear wing/trunk lid assembly strains downward onto the transducers so Corey can read out the downforce the wing is producing at any time. It's backed up by a telltale feature that captures the highest reading should Corey's vision be otherwise engaged at the critical moment-which, let's hope, it is most of the time. It's neat, laboratory-like trickery and more technical than the method used to set the wing height in the first place. That was done by fitting an old trunk lid to the car, cutting approximately a 4-inch hole in its top, stuffing Corey underneath, then having Heath drive the car up and down the street while Corey stuck his hand and arm up into the slipstream until he could sense passing through the dead air layer and into the high-velocity slipstream. The team says the downforce reading system is useful in setting the wing angle and locating the vortex generators.

Cockpit highlights include the triangulated 'cage and the remnants of the Agent 47 inner frame. Some of this is slated for removal as a weight-saving measure since the inner frame was designed for non-'caged cars and is somewhat redundant in the pure-race chassis. The Kirkey seat is augmented with a halo frame to cradle Corey's noggin during "a big one." He also wears a HANS device in this brutally fast machine. A F.A.S.T. cool-shirt box sits on the passenger floor; Corey says the cool suit is "worth two seconds a lap" by itself because it fends off the suffocating heat.

Crowning the interior is Agent 47's instrument panel. It's a heavily dished design with plenty of acreage for instruments and switches. Corey designed it with a deep hood to reduce glare on the gauges.

So far, Agent 47 has won a couple of races, was leading the competitive Southern California NASA region AIX points chase, and broke the Infiniti track record by 4 seconds. Plans are to run as much as possible, getting Corey and the team dialed into the high-speed AIX scene, including the national championships at Mid-Ohio in September. Agent 47 is interested in stepping up its trackside support program for other American Iron racers, a further indication of this team's long-term intent for this exciting series dominated by our favorite car.

Agent 47's new A-arm front suspension is a cost-contained, bolt-in suspension for approximately $2,500. A stock SN-95 spindle is used, but the "spindle eye"-where the tie rod attaches-is cut off and reattached at a more upright angle to better accommodate the likewise more vertical spindle as located by A-arms (the stock strut frontend tilts the spindle). Camber is the only adjustment at the upper A-arm; everything else is adjustable via the lower control arm. The stock steering rack is retained, and the system is said to be one of the lightest on the market.